Chuck.



J. R. SAYLOR.

CHUCK.

APPLICATION FILED JULY 8,1911. 1 ,0O8,926. Patented Nov. 14, 1911.

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JOHN R. SAYLOR, 0F POTTSTOWN, PENNSYLVANIA.

CHUCK.

Specification of Letters Patent;

Patented Nov. 14, 1911 Application filed July 8, 1911. Serial No.637,-415.

To all whom it may concern:

Be it known that 1, JOHN R. SAYLOR, a citizen of the United States,residing in Pottstown, county of Montgomery, State of Pennsylvania, haveinventedfcertain Improvements in Chucks, of which the follow- I in is aspecification.

lIy invention relates to certain improvements in chucks, andparticularly those adapted for holding work while being .finished by acutter or other tool.

The object of the invention is to provide a chuck which will firmly holdthe work and in which both jaws are operated from a single spindle. Eachjaw has a certain freedom of movement; preventing any play of the jawsof the chuck on the base.

In the accompanying drawings :Figure 1, is a face view of my improvedchuck; Fig. 2, is a sectional view on the line aa, Fig. 1; Fig. 3 is anend view; Fig. 1, is a transverse sectional view on the line bb, Fig. 1;and Fig. 5, is a detached perspective view of the two screws and thecoupling sleeve.

1 is'the base of the chuck having three bearin s, 2, 3 and 1, for thescrews 5 and 6. One 0 these screws is a right hand thread and the otheris a left hand thread. The screw 5 has a long stem 7 and is shaped to beengaged by a key or wrench by which it is turned and through whichmotion is imparted to -both jaws.

8 and 9 are two jaws having projecting members shaped to any formdesired; according to the article to be held by the chuck.

The stem 7 of the screw 5 is reduced, forming a shoulder 10, and bearingagainst this shoulder is a threaded adjusting sleeve 11 adapted to athreaded opening in the bearing 8.

The stem 12 of the screw 6 is also reduced, forming a shoulder 13 and athreaded adjusting sleeve 14 extends through the hearing 2 and restsagainst the shoulder 13. The inner end of each screw is reduced indiameter and shaped to conform to the opening in a connecting sleeve 15,which is mounted in the bearing 4. In the present instance, the openingis square and the inner ends of the screws are also square. By thisconstruction, when the screw 5 is turned, motion is also imparted to thescrew 6 through the connecting sleeve 15.

The jaw 8 has a threaded lug 16 through which the screw 5 passes and thejaw 9 has a threaded lug 17 for the reception of the screwv 6. As one ofthese screws is a right hand screw and the other is a lefthand screw,the jaws will be moved toward and from eachother, when the screws areturned.

When the article to be held in the chuck is clamped by the jaws, thenlongitudinal pressure will be applied to the screws, tending to forcethem apart and this pressure will be taken by the sleeves 11 and 14, due

to the fact that they bear against the shoulders of the respectivescrews; the screws being free to move longitudinally and independentlyone of the other. Consequently, when the work is firmly engaged by thejaws, each jaw is rigidly held as the screw bears against its particularsleeve and the sleeves can be adjusted to take up the wear so as to makea rigid grip; thus taking up all lost motion between the jaws and thebase.

The great difficulty in chucks of this type is that while the two jawsmay be rigidly connected the screw is loose in the base and,consequently, there is a lost motion between the aws and the base.

In the present instance, the base has an undercut beveled flange 18.Each side and each jaw has a lip 19 which extends over the edge of thebase so that while the jaws are free to slide on the base they cannot bedetached therefrom.

While the invention is especially adapted to hold work in a machine, itcan be used for holding any work, either in a machine or on a bench,without departing from the essential feature of the invention.

I claim:

1. The combination of a base, bearings thereon; two jaws arranged toslide on the base; two screws; one engaging the threads on one jaw andthe other engaging the threads on the other jaw; a coupling connectingthe two screws so that they will turn together, but will have a limitedlongitudinal movement; with stops against which the screws bear when thework is clamped between the jaws.

2. The combination of a base; two jaws mounted so as to slide on thebase; a right hand and a left hand screw; a coupling connecting the twoscrews so that they will turn in unison, but will have a certainlongitudinal movement; one screw engaging one jaw and the other screwengaging the other jaw; threaded sleeves through which the spindles ofthe screws extend; said sleeve being adjustably mounted in the endbearings of the base; the parts being so arranged that when one screw isturned the other will turn with it, causing the jaws to move toward andfrom each other to clamp the article and when the article is clamped,the pressure of the jaws will be directly against the sleeve on theframe, preventing any lost motion between the base and the jaws.

3. The combination of a base; two end bearings and a center bearingthereon slideways on the base; two jaws mounted on the slideways andhaving depending, threaded lugs; two shouldered screws, one a right handscrew and the other a'left hand screw; each screw having a reducedspindle forming the shoulder; a threaded sleeve in each end bearingresting against the shoulder of a screw; a sleeve mounted in the centerbearing between the two screws; the inner ends of the screws beingshaped to engage the sleeve so that both screws must turn in unison, butwill be free to move longitudinally; the spindle of one of said screwsbeing shaped to receive a key or wrench by which it is turned.

In testimony whereof, I have signed my name to this specification, inthe presence of two subscribing witnesses.

JOHN R. SAYLOR.

Witnesses:

WM. E. SHUPE, WM. A. BARR.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner oi. Patents, Washington, D. G.

